Submitted to: Journal of Natural Toxins
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/5/1995
Publication Date: N/A
Citation: Interpretive Summary: The poison, fumonisin, is found in field corn which is food for many farm animals. A study of this poison was done on rabbits by putting the poison directly in the bloodstream. It was found that the poison, fumonisin, was bad for the kidneys. The rabbit may be a useful model for studying how the poison induces bad effects on the kidneys. This information would be useful for those dealing with poisons and their effects on kidneys.
Technical Abstract: Fumonisin B1 is hepatotoxic in all species but nephrotoxicity has only been reported in rats. It is a specific inhibitor of sphinganine N- acyltransferase. Our objective was to determine the target organs for fumonisin toxicosis in the rabbit. We administered fumonisin B1 (>95% pure) iv to adult rabbits and examined selected clinical, biochemical and histological parameters for up to 5 days. In experiment 1 (pilot study), rabbits were given fumonisin B1 at 0 or 1 mg/kg daily for 5 days and then euthanized. In experiment 2 (dose-range finding study), one rabbit each was given fumonisin B1 at 0.5, 0.3, or 0.15 mg/kg daily for 4 or 5 days. Additional rabbits were given a single dose of fumonisin B1 at 1 mg/kg and euthanized on day 2 or 4. In experiment 3 (formal study), rabbits were given a single dose of fumonisin B1 at 0 or 1.25 mg/kg and euthanized on days 1, 3, or 5. Rabbits given multiple doses of fumonisin B1 were lethargic, anorectic, and had decreased urine production. Liver- and renal-associated clinical chemistry parameters were elevated. Renal lesions consisted of severe proximal tubular necrosis. Liver lesions were variable and consisted of mild necrosis, hepatocyte vacuolation, and bile stasis. The sphingosine ratio, in both target and nontarget tissues, was markedly elevated in treated rabbits. A single dose of fumonisin B1 induced renal but not hepatic injury. Therefore, the target organs for fumonisin B1 toxicity in rabbits are kidney and liver, with the kidney being more sensitive.